Semi-Cryogenic Propellant Tank

• 08 Oct 2021

Why in News

Recently, Hindustan Aeronautics Ltd (HAL) delivered the heaviest semi-cryogenic propellant tank (SC120- LOX) to the Indian Space Research Organization (ISRO).

• In 2020, HAL delivered the biggest ever cryogenic Liquid Hydrogen tank (C32-LH2) to ISRO.

Key Points

• About:
  • The semi cryo-liquid oxygen (LOX) tank - the first developmental welded hardware - is a part of the SC120 stage intended for payload enhancement by replacing the L110 stage in the existing Mk-III launch vehicle.
    • GSLV Mk III is a three-stage heavy-lift launch vehicle developed by ISRO. The vehicle has two solid strap-ons, a core liquid booster and a cryogenic upper stage.
• Cryogenic Engine:
  • A cryogenic engine/cryogenic stage is the last stage of space launch vehicles which makes use of Cryogenics.
    • Cryogenics is the study of the production and behaviour of materials at extremely low temperatures (below -150 degree Centigrade) to lift and place heavier objects in space.
  • A cryogenic engine provides more force with each kilogram of cryogenic propellant it uses compared to other propellants, such as solid and liquid propellant rocket engines and is more efficient.
  • It uses Liquid Oxygen (LOX) and Liquid Hydrogen (LH2) as propellants which liquefy at -183 deg C and -253 deg C respectively.
• Semi Cryogenic Engine:
  • Unlike a Cryogenic engine, a Semi Cryogenic engine uses Refined kerosene instead of liquid hydrogen.
  • The liquid oxygen is used as a Oxidiser.
    • That’s the advantage of using a Semi Cryogenic engine as it requires Refined Kerosene which is lighter than liquid fuel and can be stored in a normal temperature.
  • Kerosene combined with liquid oxygen provide a higher thrust to the rocket.
  • Refined Kerosene occupies less space, making it possible to carry more propellant in a Semi Cryogenic engines fuel compartment.
  • A semi cryogenic engine is more powerful, environment friendly and cost effective as compared to a cryogenic engine.

Source: ET